Cytotoxic effects of 1-beta-D-arabinofuranosylcytosine and 6-thioguanine in vitro on granulocytic progenitor cells. We have utilized an in vitro clonogenic assay of mouse and human marrow granulocytic progenitor cells to determine the cytotoxic effects on granulopoiesis of the chemotherapeutic agents 1-beta-D-arabinofuranosylcytosine (ara-C) and 6-thioguanine. Concentration- and time-dependent decrements to plateau levels of granulocytic colony-forming capacity occurred. The sequence of drug administration was important and synergistic cytotoxicity was noted when certain schedules of ara-C and 6-thioguanine combinations were used. Endotoxin-stimulated colony-forming cells had increased sensitivity to the in vitro ara-C exposure. High or intermittent doses of ara-C demonstrated enhanced cytotoxicity when short exposure times (1 to 8 hr) were utilized, whereas low doses were markedly cytotoxic with prolonged exposure (10 days). Normal and leukemic human colony-forming cells had similar susceptibility to the cytotoxic effects of ara-C. Exposure of granulocytic precursors to these drugs in vitro produced effects similar to those previously reported with in vivo drug administration. These techniques appear applicable for providing improved screening models to evaluate chemotherapeutic regimens for clinical use.


Randomized clinical comparison of daunorubicin (NSC-82151) alone with a combination of daunorubicin, cytosine arabinoside (NSC-63878), 6-thioguanine (NSC-752), and pyrimethamine (NSC-3061) for the treatment of acute nonlymphocytic leukemia. Sixty-six newly diagnosed patients with acute nonlymphocytic leukemia received either daunorubicin alone or a combination of daunorubicin, cytosine arabinoside, 6-thioguanine, and pyrimethamine for remission-induction therapy. The two treatment groups were comparable with respect to the two major prognostic factors in this disease, which were age and presence or absence of infection on admission. The two therapies produced similar results with respect to CR rate and median survival results. Single-agent therapy was associated with less frequent utilization of hospital inpatient facilities and fewer platelet transfusions. The four-drug combination did not decrease the incidence of meningeal leukemia. Patients who achieved CR were treated with two half-dose consolidation courses of the successful remission-induction regimen. Subsequently, all patients received cyclophosphamide and guanazole monthly for maintenance therapy. Median durations of remission for both induction-treatment groups were similar (6.8 and 5.6 mos). The therapeutic results with the single agent in this study were not inferior to those obtained with the drug combination tested, as well as most other previously reported combinations of antileukemic drugs.


Dental insurance and equity of access to dental services. The first-year consequences of national dental insurance, introduced in Sweden in 1974, are examined here from the point of view of social justice. The concept of equity of access in medical care is discussed. In a local survey, a comparison is made between use of dental services in 1972, 1973, and 1974. The results indicate that the fewer people visited the dentist after the implementation of the insurance than before. Other evidence supports this conclusion. People traditionally considered to be underprivileged as to dental care were compared with other people. One underprivileged group, edentulous persons, received more treatment after the insurance was instituted than before.


Utilization of dental services in the adult Danish population 1975. Lack of information on the dental behavior of adults in Denmark has become a major problem in the national planning of dental services. The purpose of this study was to establish the pattern of utilization of dental services among adult Danes (aged 15 and above). A three-stage cluster sampling design covering the total adult population of Denmark was used to draw a representative sample comprising 1,600 persons. Household interviews by trained interviewers were carried out. Of the adults interviewed, 58% reported yearly dental visits the last 5 years, 32% had not seen a dentist or only when in pain, and 10% went irregularly. Differences according to place of living, age, sex, occupation and school dental care were found. 63% of those who had seen a dentist reported bad teeth or were edentulous with or without dentures. 10% reported fear, 9% had good teeth and 5% reported economic difficulties. The most frequent treatments at the latest dental visit were cleaning and filling for the regular patients and extractions and dentures for the nonregular patients. A multiple classification analysis revealed that the number of teeth was the strongest predictor for dental services, with the following predictors in descending order: age, occupation, place of living, economy, sex and school dental care. These variables could explain 58% of the variation in utilization.


Testing the internal and external validity of a simplified dental caries index on an adult population. This analysis of a caries index, proposed in 1966 to WHO as a simplified method of measurement, as tested on a 16- to 45-year-old population who were seeking dental care at the University of Minnesota School of Dentistry revealed several weaknesses associated with the index. An analysis of the external validity of this index, a comparison with subjects' DMFS scores, revealed a correlation coefficient of 0.71. Although the index purports to measure the prevalence and severity of dental caries by dividing the dentition into five zones representing increasing severity of dental caries experience, an analysis of this index's internal validity, i.e. whether these five zones truly represent a rank-order scale of severity, revealed misclassification rates of from 21% for the total population up to 44% for a subgroup. When zones were recombined to reduce the misclassification rates, the descriptive capabilities of the index were greatly reduced as most subjects were then classified in only one or two of the zones.


A comparative radiographic investigation of caries prevalence in Danish schoolchildren. In order to assess the prevalence of untreated caries in two groups of Danish 7th grade (13- to 14-year-old) school children in a blind study, a radiographic investigation was carried out. Only half of the children (394) had received regular school dental care during their years of attendance of primary school; the other children (368) had not. A bitewing radiograph of the right side of the mouth of each child was taken, employing a standardized technique. The radiographs were read without the examiner knowing the group identity of the radiographs. The criteria for discarding poor radiographs, teeth, and tooth surfaces are described. Some of the radiographic results are compared with the clinical caries score of the same group. Most of the radiographs without untreated caries were found among those of the children who received school dental service. Uncertainty of method in connection with radiographic investigation is discussed.


Effect on caries experience of lifetime residents after 10 years of fluoridation in Townsville, Australia. An oral health survey was conducted in the tropical city of Townsville 10 years after its water supply was fluoridated to a level of 0.7 parts/106. The results of the calibration of examiners prior to the survey are presented. Checks on the consistency and comparability of the results obtained by each examiner during the survey show that the results are reliable and reproducible. Dental caries experience of both primary and permanent teeth was found to be significantly lower in Townsville than in 16 non-fluoridated towns. Comparisons are also made between the prevalence of caries in Townsville and four naturally fluoridated towns.


The effect of various plaque control measures on gingivitis and caries in schoolchildren. The aims of the present study were (1) to analyze the separate effects on plaque, caries, and gingivitis of several measures (oral hygiene instruction, professional tooth cleaning with mechanical instruments, topical application of sodium monofluorophosphate - MFP) which have been incorporated in a prophylactic treatment program, described by AXELSSON & LINDHE1, and (2) to prevent caries and gingivitis by applying the combined treatment but replacing the professional mechanical tooth cleaning with chemical cleaning using a chlorhexidine-containing gel. 164 children, 13-14 years old, divided into four groups, participated in a 2-year trial. All participants were recalled once every 2nd week for preventive treatment provided by dental nurses. During the 1st year Group 3 and 4 received prophylactic treatment identical to that described by AXELSSON & LINDHE1. During the 2nd year the professional tooth cleaning was omitted but oral hygiene instruction was given every 2nd week. During the 1st year Groups 1 and 2 were treated with 0.5% chlorhexidine but during the 2nd year they were subjected to professional tooth cleaning with mechanical instruments. Throughout the trial Groups 1 and 3 rinsed once every 2nd week with a 2% MFP solution. The results showed that by oral hygiene instruction and frequently repeated professional tooth cleanings it was possible to substantially reduce the frequency of gingivitis and prevent caries. When this treatment was used, mouthrinsings with 2% MFP had no additional effect on caries. The substitution of the mechanical cleaning procedure with topical application of a 0.5% chlorhexidine gel failed to (1) remove supragingival plaque accumulations, (2) reduce the frequency of gingivitis, and (3) retard the rate of caries development. The data also revealed that interdental cleaning with mechanical instruments was of decisive importance in the prevention of approximal surface caries.


Pure red cell aplasia. A preleukemic state.


Currently and/or certified.

Currently and/or certified.


Student evaluation in courses in dental education.


The Hawthorne effect.

The Hawthorne effect.


The constitutionality of state restrictions imposed upon the dental hygiene education system.


National trends in education affecting dental auxiliary education.


Training program for dental auxiliary educators.


Criterion related and evaluated instruction in undergraduate pharmacology.


Student controlled chairside assisting training program.


Primary dental care: an educational methodology for dental hygiene students.


Professional ethics in dental auxiliary education.


Academic freedom.

Academic freedom.


Curriculum survey of dental hygiene graduates.


Needed--peer review for dental students.


December--last chance for year-end tax planning.


Notes and comments.

Notes and comments.


Who cares for your office if your're disabled?


Puzzled by missing cash?

Puzzled by missing cash?


The governor is coming.

The governor is coming.


Deceived for those receivables?

Deceived for those receivables?


Let's help the physician care for the patient.


Ever faced a night in jail?

Ever faced a night in jail?


The letter you owe your family.

The letter you owe your family.


The hygienist's broad role in examination, counseling.


How health manpower bill affects dentistry.


For the 'Marathon Man', a dental nightmare.


The 'difficult' patient and tongue thrust.


Magic offers key to gaining rapport with young patients.


Endodontic technic for blunderbuss teeth.


Prescribing dental drugs: generic or brand names?


Scrapbook holds collection of humorous patient comments.


Beginning a practice: how one new dentist did it.


Sucrose, neutrophilic phagocytosis and resistance to disease.


'Examination' by auxiliaries, but 'diagnosis' by dentists.


Artwork transforms waste-space closet into 'Toothdom Castle'.


Interior, exterior blend in 'atmosphere of warmth'.


Polyglutamate forms of folate: natural occurrence and role as substrates in mammalian cells.


Chronic myeloid leukaemia with skin infiltration: a case report.


President's message.

President's message.


Planning your AGD mastership.

Planning your AGD mastership.


Case report: hemi maxillary hypoplasia, combined orthodontic - oral surgical approach.


An orthodontic challenge.

An orthodontic challenge.


The fringe benefits of being a member of the FOA.


An understanding of the biomechanical factors in light wire treatment.


Thyroid hormone-vitamin treatment: a dental and medical evaluation.


Four little, three little, two little Indians, one little Indian boy.


Removal of salivary deposits by commercial denture cleansers.


A space-regaining procedure for the early mixed dentition.


I.J.O. Diagnostrix.

I.J.O. Diagnostrix.


Congratulations--Charlie Berman we're all proud of you!


Radiographic features of bone in several strains of laboratory mice and of their tumours induced by bone-seeking radionuclides. The natural radiographic appearance of the various bones of the skeleton are described for several strains of laboratory mice. The Harwell substrains of CBA, A and 101 are generally similar and become osteoporotic on ageing. Harwell C57BL have similar, but more delicately chiseled, bones. Harwell C3H mice have bones with stouter cortices and may show osteosclerosis on ageing. CF1 females (donated by Dr M. Finkel) showed osteosclerosis and osteophytic outgrowths when aged. NMRI mice (donated by Dr A. Luz) appeared larger than the pure-strain Harwell mice. In general, mouse bones are simple tubular structures with an ivory cortex and a marrow cavity. Cancellous trabecular bone is scanty, even in vertebrae, flat bones and the metaphyses of long bones. Bone-seeking radionuclides administered to mice lead to skeletal tumours: (a) osteosarcomata, which are commonly radio-opaque to a variable degree owing to calcified tumour bone, but which may be osteolytic, (b) primitive mesenchymal (angio-) sarcomata which are non-osteogenic and osteolytic, (c) fibrosarcomata--which also are osteolytic--and to local or general lymphomata from irradiation of parental cells in bone marrow, but no special radiological features have been found associated with these last-named tumours.


Choices.

Choices.


Fluoridation debate coordinated by Dr. Jack Tweedle: Pro.


Fluoridation debate coordinated by Dr. Jack Tweedle: Con.


Your estate--how to preserve it. Joint tenancy (some pointers and advice).


IRS...the paper tiger.

IRS...the paper tiger.


Guidelines of N.J. Dental Association for school dental programs.


Combined therapy for endodontic-periodontic lesions.


On warm and cool colors.

On warm and cool colors.


Materials for school dental programs.

Materials for school dental programs.


Your will...the essential estate planning device.


[Approximating private practice in a dental school].


Know your colleague. Dr. Joel Abraham - car collector.


Endodontic implants.

Endodontic implants.


The Pension Reform Act and the professional corporation.


Congressman Maguire answers questions of interest to members.


The perception of dentists by dental and non-dental populations.


Harry Archer and the dragon (or conquering the silent killer).


Why set up a trust?

Why set up a trust?


Understanding ultraviolet light.

Understanding ultraviolet light.


Can patients inherit periodontal disease? You can help discover the answer.


Dental photography.

Dental photography.


Who practices dentistry in your office?

Who practices dentistry in your office?


Controversies in dentistry: tongue-thrust therapy.


A dental dilemma.

A dental dilemma.


Animal experimentation to develop an endodontic-endosseous implant.


The simplification and increased precision of occlusal adjustment by selective tooth grinding--the "True-Mark" technique.


An interview with Dr. Ralph Kaslick.

An interview with Dr. Ralph Kaslick.


[Bacterial accumulation on silicate and composite materials]. It was shown in a previous study that more plaque accumulates on composite filling materials than on silicate cement and amalgam. The purpose of the present investigation was to compare the accumulation of Streptococcus mutans on silicate cement and on composite material by scanning electron microscopy. Whether the adhesion was dependent on the presence of sucrose was also tested. Round disks, 6 mm in diameter, were made from the two materials. The disks were submerged in media with and without sucrose and inoculated with S. mutans OMZ 176. The disks were removed after 1 or 30 minutes, rinsed in saline and prepared for SEM. Along the diameter of each disk pictures were taken at similar intervals. From a total of 48 pictures from each material 18 pictures were selected at random and the number of microorganisms counted. The results indicated that bacteria initially adhered to both silicate and composite in about the same number. The presence of sucrose did not influence the initial adsorption. After 30 minutes bacteria were scarcely found on silicate, whereas large clumps of bacteria were attached to the composite. Sucrose increased bacterial accumulation on composites but did not affect the adherence to silicate cement.


Tongue fissures. A classification and comparative prevalence study among 825 European Caucasian and 605 Xhosa Negro school children. Six distinct patterns of tongue fissuring have been observed: plication, central longitudinal fissuring, double fissures, transverse fissures arising from a central fissure (type "A"), transverse fissures without a central fissure (type "B") and lateral longitudinal fissures. Some tongues exhibited more than one pattern. There was a significant correlation between double fissures and central longitudinal fissuring (P less than 0.002) but not between other forms of fissuring. No significant relationship was found between the occurrence of atrophic lesions and the prese-ce of fissuring. Significant differences were found between the prevalences in Xhosa and Europeans for central longitudinal fissuring, double fissures and both types of transverse fissures but not for plication. No significant differences were found between males and females and in the age distribution for those with and those without each type of fissuring. It is suggested that most tongue fissuring seen in children should be considered variations in normal anatomy rather than an abnormality.


Time-saving band driving technique.

Time-saving band driving technique.


The effect of antero-postero incisor repositioning on the palatal cortex as studied with laminagraphy.


The modular self-locking appliance system. Part 3. A variation in the combination technique.


Five year clinical evaluation of the Andrews straight-wire appliance.


Local anaesthetics--understanding the problems.


The dental status of a chronically disabled section of the community: a study of 139 patients suffering from rheumatic diseases.


The human face and the chaning face face of dentistry.


Periodontal discriminatory ability in human subjects with natural dentitions, overlay dentures and complete dentures.


Röntgenologiese diagnose.

Röntgenologiese diagnose.


The role of the dentist in the management of the cleft palate patient.


Policy implications of "a new perspective on the health of Canadians".


[The shadow of the great Fauchard grows dim].


[The control of the professional competence: a delicate but necessary measure].


[Preprosthetic periodontal treatment of clinically reduced crowns].


Finite element stress analysis of the crowns of normal and restored teeth. Stress distributions are presented for a normal and a restored mandibular second premolar under masticatory-type forces. These were obtained using the finite element method of stress analysis applied to two-dimensional models. The effect of the relative stiffness of the materials is examined in each instance.


Influence of amalgam, alloy, and Hg on the in vitro growth of Streptococcus mutans: III. Effect of specimen age and composition. We will now summarize the conclusions from parts I, II and III of this study. A test procedure has been developed that provides a simple, quick, and nondestructive means of monitoring the in vitro growth of S mutans in the presence of amalgams and alloys. The spectrophotometric readings are related in a simple way to growth expressed as dry weight of bacteria and metabolic products. Results are expressed as growth relative to controls which represent bacteria growing under identical conditions but not in contact with metals. The %RA60 value that represents growth after 60 hours relative to controls is used as a measure of growth in the presence of alloys or amalgams. Spherical, fine cut, and dispersion alloys were studied as well as amalgams prepared from these alloys. The dispersion alloy inhibits growth less than the spherical alloy which in turn inhibits growth less than the fine cut alloy. The results for amalgams prepared from the alloys are reversed. At an aging time of two hours, dispersion alloy amalgams inhibit growth more than spherical alloy amalgams and fine cut alloy amalgams. Aging time of amalgams greatly influences the growth inhibition. Immediately after trituration growth is inhibited, but this inhibition is lost with aging. Different types of amalgams seem to lose growth inhibition at different rates. Hg composition in the range of 48 to 52% seems to have little effect on growth inhibition. It remains for clinical studies, which are concerned with the incidence of secondary caries associated with amalgams, to demonstrate that the age and nature of the amalgam are significant.


Cariostatic activity of calcium glycerophosphate in hamsters: topical vs dietary administration. Two experiments were conducted to determine if calcium glycerophosphate administered continuously in a diet or intermittently as a single daily topical application to teeth had an anticaries potential in young hamsters that were fed a cariogenic diet. The hamsters were inoculated with a caries-conductive streptococcal strain. Within the 60-day experimental period, results of these evaluations indicated calcium glycerophosphate significantly reduces caries when fed in the diet at levels of 1% and higher, and significantly reduces caries when applied topically at levels of 2% and higher. There were no observable differences in plaque formation among treatments.


Surface properties of hydroxyapatite: I. The effect of various inorganic ions on the electrophoretic behavior. The zeta potential of hydroxyapatite (HA) at a constant pH depends on the type of acid used. Fluoride ions increase the charge density and make the surface less prone to attack by acid or alkali. Sn2+ and Th4+ ionic complexes with fluoride ions and increase the uptake of fluoride by HA.


Identification of the cultivable bacteria in dental plaque from the beagle dog. Fifteen different genera of microorganisms were isolated from the 27-month-old plaque of two beagle dogs. They were as follows: Pseudomonas, Proteus, Neisseria, Escherichia, Staphylococcus, Streptococcus, Lactobacillus, Nocardia, Actinomyces, Corynebacterium, Micrococcus, Microbacterium, Brevibacterium, Arthrobacter, and Kurthia. The dog plaque was characterized by a low number of streptococci and the presence of several noncarbohydrate-fermenting organisms.


Analysis of the dextranase activity produced by an oral strain of Bacteroides ochraceus. An anaerobic, gram-negative, dextranase-producing filamentous bacterium isolated from human dental plaque has been identified as a strain of Bacteroides ochraceus. The inducible intracellular dextran-degrading activities produced by this microoranism can be fractionated into endohydrolytic and exohydrolytic enzymes with distinct pH optima. These enzymes reduce the apparent rate of glucan production from sucrose by the dextransucrase produced by Streptococcus mutans and consequently may influence the in vivo production of polysaccharides involved in plaque accumulation and metabolism.


Microprobe analysis of a Au-containing alloy and its amalgam. Under near-equilibrium conditions, an alloy ingot containing approximately 64% Ag, 26% Sn, and 10% Au was found by X-ray diffraction to consist of large grains demonstrating the gamma (Ag-Sn) structure. Microprobe analysis of these grains showed a 64.2% Ag, 25.3% Sn, and 10.5% Au composition with very small amounts of AuSn2 and AuSn4 segregated at the grain boundaries. When this alloy is manufactured in the form of rapidly colled spherical particles, X-ray diffraction shows both beta (Ag-Sn) and gamma (Ag-Sn) structures with Au substituting for Ag, and microprobe analysis demonstrates a segregation of small high Sn, high Au areas having a AuSn2 composition. When Hg is mixed with these spherical particles, gamma1, some gamma2, and Sn-Au phases (AuSn2 and AuSn4) form. The Au that combines with Sn seems to come from the beta or gamma phases rather than from the Sn-Au segregations in the alloy. The small amount of the gamma2 phase that is initially formed apparently disappears after a short period of time although there is some question as to whether a very small amount may still remain. The Ag-Hg hase (gamma1) is essentially the same as found in conventional amalgams as is the small amount of gamma2 initially formed. Furthermore, a nonequilibrium state seems to be necessary for the early and possibly complete elimination of gamma2. In the as-cast condition, after a period of time at 37 C, A Ag-Hg-Sn phase (beta1) is formed that is similar to that found in conventional amalgams that serve as restorations in the mouth for a period of time. However, in the 135-annealed amalgam, no beta1 appears.


Optical method for articulator comparison and study of occlusal determinants. A method of articulator comparison and a technique demonstrating the effects of three occlusal determinants were demonstrated and proved successful. The techniques used could be used in dental research circumstances and in dental schools as a means to study the determinants of occlusion.


Erythrocyte velocity in vascular networks of young noninflamed dog gingiva. Measurements of erythrocyte velocity in vascular networks of noninflamed gingiva of deciduous canines of four young dogs were obtained using vital microscopy and high-speed cinephotomicrography. Mean erythrocyte velocity in small gingival vessels was 1.59 +/- 0.29 mm/sec. Differences in erythrocyte velocity of vessels comprising a gingival microcirculation and of vessels within different gingival samples were not significant.


Effects of dietary fats on the fatty acid composition of enamel and dentinal lipids of rabbit molars. The effect of dietary fats such as butter, lard, cottonseed oil, and hydrogenated cottonseed oil on the fatty acid composition of enamel and dentin lipids of rabbit molars was studied. The enamel and dentin of molars of all of the rabbits contained a variety of fatty acids, palmitic, stearic, oliec, linoleic, and eicosapentaenoic being the major ones. Enamal lipids were more unsaturated than dentinal lipids in all of the groups. A significant difference was noticed in the fatty acid composition of both the enamel and dentin between these four groups of rabbits. Linoleic acid content was highest in both the enamel and dentin lipids of rabbits fed cottonseed oil. There was no marked difference in the saturated-unsaturated fatty acid ratio in both the enamel and dentin among rabbits fed cottonseed oil, lard, and butter. It is concluded that tooth lipids are responsive to diets and are in direct equilibrium with dietary components.


Magnesium in bone mineral: an in vitro study. The solubility of magnesium in bone mineral from control and magnesium-dificient rats receiving varying fluoride intakes was assessed. Evidence for the existence of a fluoride-related pool of skeletal magnesium possessing a diminished solubility was obtained.


Combined ulcerogenicity of aspirin and indomethacin in the rat.


Clinical assessment of the marginal breakdown of conventional alloys adjacent to a dispersion alloy.


Effect of mycophenolic acid on healing of skin and buccal mucosal wounds in rats.


Caries experience in deciduous and permanent dentition of the same individuals. Caries of the permanent first molars of 5-year-old children was found to be associated with caries of their diciduous teeth. The sample consisted of 220 children whose permanent first molars had erupted. They were selected out of 965 children who were a representative sample of children attending compulsory kindergartens in Jerusalem, 1971.


Calcification of membranes isolated from Bacterionema matruchotii. Lytic cultures of Bacterionema matruchotii were found to release vesicular membranes into the medium which could be obtained virtually free of other cell structures by differential centrifugation. Suspension of the membrane fraction in a metastable calcium phosphate solution resulted in the formation of both amorphous mineral and hydroxyapatite. Examination by electron microscopy showed that mineralization was associated with the membrane bilayers. The results provide further evidence that calcification of B matruchotii is related to intracytoplasmic membranes.


Enhancement of the antiplaque value of antibacterial agents by enamel conditioning methods: III. Animal results. A 1:1 water-paste slurry of a placebo and several experimental dentifrices was swabbed daily for six weeks on the teeth of albino rats, and the plaque collected on the teeth was measured in vivo first before the treatments began and one, two, three, and six weeks after. The results indicate that adding a suitable antimicrobial agent to a placebo dentifrice markedly reduced plaque accumulations on the teeth brushed with that product. When an enamel-conditioning vehicle was used instead of the placebo, the antiplaque effectiveness increased severalfold. It was concluded from the two first articles of this series 1,2 that adding antibacterial agents to enamel-conditioning systems resulted in the incorporation of the antimicrobial compound into enamel treated with these systems, and that enamel treated in such a fashion acquired marked antibacterial properties of its own. The data reported in this article support a third conclusion, namely, that the enamel-conditioning-antibacterial systems have a considerable antiplaque effect in laboratory rats.


Growth of transplants of the rat cranial base.


A porous and potentially tough dental implant material.


Fracture of human dentin: a high resolution scanning electron microscope study.


Parent-child similarities in dental caries rates.


Standardization of value profiles of dental students and dental faculty. This study used the Allport-Vernon, Lindzey1,2 Study of Values to establish standardized norms for dental populations, and examined the relationship among freshmen, seniors, and full-time and part-time faculty. The normative data indicate that there is a similarity in general patterns for all groups. The dental student population sampled have higher scores on aesthetic and social values than their counterparts ten years ago.


Proliferation of cells in vitro after long-term exposure to endotoxin.


Anodic polarization of new dental amalgams.


Clinical evaluation of a root canal cement that contains paraformaldehyde: comments on article.


Study of tooth emergence in British blacks and whites.


Evaluation of a simplified caries index for use by the US Army Dental Corps. The evaluation of a simplified caries index was undertaken to determine the validity and reliability of the index when applied to a military population. Although certain internal assumptions of this simplified caries index were not upheld, the index did rank order the populations by severity of caries experience when compared to the DMFS index. High interexaminer and intraexaminer reliability scores were demonstrated.


[Insurance firm's audacity].

[Insurance firm's audacity].


Au-amalgam alloy: effect of annealing and splat cooling.


Change is not easy.

Change is not easy.


Women in dentistry.

Women in dentistry.


No shortage of dentists.

No shortage of dentists.


Measurement in vitro of enamel abrasion by dentifrice. An in vitro method of measuring the abrasivities of dentifrices and abrasive powders on human dental enamel has been developed. The method, based on a proven dentin abrasivity method, records, in absolute terms, the abrasive effects of brushing flat, nonirradiated, enamel specimens beneath an aqueous slurry of the test material with the use of a surface profile meter.


Downgraded by Marathon Man.

Downgraded by Marathon Man.


Videotape modeling of the child dental patient. One week before their first dental visit, 36- to 60-month-old children were shown a videotape to model their behavior in the dental situation. The behavior was then rated for three visits. The children who had been modeled did not behave significantly better than either children who had no previous contact with the dental setting or children who had visited the reception room one week before their first dental visit.


Standards of excellence.

Standards of excellence.


EDDAs--the political implications.

EDDAs--the political implications.


A new abrasive applicator for human enamel biopsy procedures. Experiments were performed that demonstrated that the felt cylinder usually used to obtain abrasive biopsy specimens did not uniformly remove enamel from rounded or irregular enamel surfaces in the window area. A foam-silicone rubber laminate was developed to replace the felt cylinder. This resulted in greater uniformity of abrasion over the enamel surface within the biopsy window area and better operator handling characteristics.


Examiner standardization for caries studies. Examiners in clinical control programs customarily undergo an intensive period of training to standardize their interpretation of diagnostic criteria. Data are presented summarizing examiner error rates in calibration examinations and reversal rates in a field study.


Utilization of auxiliaries and attitudes of dentists toward the delegation of duties. Employment of auxiliaries by dentists is high and duties performed by those auxiliaries vary. The auxiliaries' years of experience prior to their present job is low, but tenure in the job is not as low since over 30% have been employed five years or more. Regardless of the category of dentists being considered (type of practice, year of graduation, employment of auxiliaries), the great majority of dentists (over 95%) do not think cutting soft or hard tissue should be delegated. Beyond these two procedures, however, the tables show considerable variation in attitude toward delegation when year of graduation and employment of auxiliaries are considered. Other procedures that a substantial portion of the profession does not believe should be delegated are administering local anesthetic agents; placing and finishing resins, composites, and silicate restorations; placing amalgam restorations; and carving and finishing amalgam restorations. The impact of these attitudes on delivery of care should be directed particularly toward the attitudinal differences occasioned by graduation year and employment of auxiliaries, since the proportion of graduates shifts regularly and employment of auxiliaries is increasing.


Comparison of interproximal carious lesion detection in panoramic and standard intraoral radiography. Panoramic radiographs used alone were ineffective diagnostic aids in the detection of early interproximal carious lesions, particularly enamel lesions. The best radiographic survey in terms of numbers of enamel interproximal carious lesions detected was the combination of periapical plus posterior bitewing radiographs. For interproximal lesions extending through the enamel and into the dentin, all combinations except panoramic radiographs used alone showed comparable usefulness. For lesions involving the enamel and dentin, and extending half way or more from the dentinoenamel junction to the pulp, there generally were no significant differences between any of the combinations.


Considerations in dental treatment of children with ectodermal dysplasia. Characteristics of ectodermal dysplasia and agammaglobulinemia have been presented and a case in a 6 1/2-year-old boy having both genetic diseases is reported. The child had been mocked by his peers at school. A maxillary overlay denture and mandibular cast denture were constructed using a Baker bar and cast gold thimble crowns. The parents reported that the patients personality changed favorably after dental treatment was completed. He is now 13 years of age, has had his dentures replaced once, and enjous a rather active life with the aid of antibiotics and supplemental globulins.


Dental caries experience in the deciduous dentition of rural Guatemalan children ages 6 months to 7 years. A study of 528 Guatemalan children indicated that caries prevalence in the deciduous dentition was twice as great as but in the permanent dentition was similar to that for US white children. This is a repeated observation for children of some preindustrial societies. Caries experience was significantly greater in boys. Until 4 years of age, caries attack was greater in the anterior segment of the oral cavity; linear enamel hypoplasia was a predisposing factor.


Patient anxiety and dental practice.

Patient anxiety and dental practice.


Course listing for January through June 1977. Council on Dental Education.


Oral health of patients with cystic fibrosis and their siblings. Caries prevalence, oral hygiene index, submandibular gland hypertrophy, occlusion, dental hypoplasia, and staining of permanent teeth were evaluated in 63 patients with cystic fibrosis (CF) who were maintained on a regimen of broad-spectrum antibiotics and oral pancreatin, and the findings were compared with those of their near-aged siblings. Gland hypertrophy and dental staining were increased in patients with CF whereas caries was significantly decreased. No other significant differences were found.


Fluoride deposition in human enamel in vivo from professionally applied fluoride prophylaxis paste. Deciduous teeth were collected from children who received professional prophylaxis with an acidulated phosphate-fluoride (APF) or placebo paste and were analyzed to determine fluoride uptake. Enamel fluoride level was increased by the APF paste approximately 300 ppm at a depth of 2.5 micrometers during the first month after the prophylaxis was administered, after which it returned to pretreatment levels.


Formation of calcium phosphates in saliva and dental plaque. This is an X-ray diffraction study of the mineral phases in saliva and early dental plaque. The salivas studied came from patients with cystic fibrosis (CF), those with asthma, and heavy and light calculus formers. One-week old plaque was studied from individuals who are heavy, moderate, and light calculus formers.


Estimating examiner consistency with DMFS measures. Within- and between-examiner reliability estimates were considered for standardization data. However, within-examiner stability was demonstrated to be the important measure of examiner consistency in the clinical trial because it directly affects the precision of the study. Finally, an argument is also made against the use of reversal rates in the assessment of examiner consistency.


Ion probe study of fluorine gradients in outermost layers of human enamel. F concentrations in the outermost layers of human tooth enamel were studied with the aid of a secondary ion microanalyzer. Concentration profiles were recorded in continuous sputtering analysis from the surface down to a depth of about 0.3 micrometer. Samples previously subjected to topical fluoride treatment were compared with reference specimens. In some samples, the results were compared with those obtained at greater depths by macroscopic etching analysis.


Urinary infection in children in general practice: a laboratory view. Children with urinary infection present at first to their general practitioners; paediatricians to whom they may be referred must assess the validity of the bacteriological diagnosis made at that time. With this in mind an analysis has been made of the laboratory findings in 2204 mid-stream urine specimens from 1586 children between the ages of two and 12 years examined at the request of their general practitioners during the course of one year. The contamination rate was shown to be low; 8% of the specimens from boys and 19% of those from girls showed definite infection, and the ratio of infections in boys to girls was 1:4. There was a considerable difference in the infecting organisms in the sexes. Analysis of the reasons for sending the specimens revealed that a high percentage of children who complained of urinary symptoms did not have infection. Of the children complaining of enuresis only there was a significantly greater incidence of infection in girls than in boys. In the absence of any large studies of urinary infection in domiciliary practice, data from a laboratory which serves many practitioners can contribute to knowledge of the disease.


Epidemiological studies on the 1967-1968 foot-and-mouth disease epidemic: the reporting of suspected disease. From an analysis of the telephone reports in ten FMD Control Centres in the West Midlands, the veterinary officers' reports on each outbreak, the farm patrol reports and the daily number of outbreaks announced on the 17.50 h B.B.C. T.V. News, it would appear that the reporting of suspected outbreaks was indirectly related to the local disease activity. Private veterinary practitioners reported older cases of FMD at the beginning and end of the epidemic than in the middle.


Neonatal infection due to Salmonella worthington transmitted by a delivery-room suction apparatus. An outbreak of diarrhoea due to Salmonella worthington in five newborn babies, 5 weeks after a similar outbreak in 13 babies for which no cause had been found, occurred in the nursery of a maternity ward. The source of infection was traced to the contaminated rubber tubing of a mechanical suction apparatus. S. worthington was isolated from the rubber tubing and the Y connexion of the suction apparatus from which all the five infected babies had received suction. Reflux of contaminated amniotic fluid into the sterile catheter connected to the apparatus some time before use could have been the means of introducing the infected material to the oropharynx of the newborn babies, and amniotic fluid, acting as a good medium to support the growth of S. worthington, might be responsible for the long-lasting contamination.


The size of airborne dust particles precipitating bronchospasm in house dust sensitive children. We have assessed the effect of house-cleaning procedures on changes in airborne dust and bacteria counts and correlated these with respiratory function tests in 14 children with bronchial asthma who were known to have developed attacks at home, and who had positive skin tests to house dust and the house-dust mite. We have demonstrated that after cleaning procedures a positive and statistically significant correlation exists between the increase in the numbers of small particles, 2 mum. and less in diameter, in the environment, and reduction in mean peak flow. This indicates that particles of this size penetrate the bronchial tree and are the causative factor in the genesis of bronchospasm.


WRL 105 strain live attenuated influenza vaccine; comparison of one and two dose schedules. Haemagglutinating inhibiting antibody (HAI) responses were determined and clinical reactions recorded in 162 adult volunteers who received either 1 or 2 intranasal doses of 10(7-0) EID50 WRL 105 strain live influenza vaccine or placebo. After administration of a single dose of vaccine significant antibody responses were obtained in 69 (70%) of 98 volunteers with initial antibody titres of less than or equal to 1/20. Of the 70 volunteers who received a second dose of vaccine, 62 provided a further post-vaccination sample of serum, and only 3 (4-8%), who had not responded to the first dose of vaccine, produced a significant antibody response. Local, upper respiratory and constitutional symptoms were recorded more frequently after the administration of a first dose of vaccine than after placebo or a second dose of vaccine. The symptoms were of a minor nature except in one volunteer who, after the first dose of vaccine, developed influenzal symptoms followed by bronchitis.


Isolation of salmonellas from sewage-polluted river water using selenite F and Muller-Kauffmann tetrathionate. Selenite F broth and a modified Muller-Kauffmann tetrathionate broth were investigated using sewage-polluted natural water as inocula. The modification of the tetrathionate medium was necessary as commercial alternatives would not allow multiplication of small numbers of salmonellas. The wide range of molar concentrations in different tetrathionate broths was emphasized. Selenite F broth was more efficient than Muller-Kauffmann tetrathionate broth, in our hands, with the material tested. Direct inoculation of the enrichment media was used. Each of the two media examined had a bias towards selection of certain serotypes. If possible, both enrichment broths should be used to obtain maximum information.


Quality control of the isolation rate of pathogens in medical microbiology laboratories. Two statistical analyses are suggested to compare the success rates in isolating and identifying pathogenic organisms from specimens achieved by different laboratories participating in a quality control scheme. An example is given in which the analyses are applied to 25 laboratories that received 30 simulated specimens.


Salmonella crossness--a new serotype containing a new comatic (O) antigen, 67. A new salmonella subgenus I serotype is described. Strein C.S. 1608/73, serotype 67:R:1, 2, was isolated from activated sewage sludge and was assigned the name S. crossness. The serotype is biochemically atypical in its ability to utilize sucrose and this ability appears to be controlled by a transferable plasmid.


The treatment of soil infested with the human whipworm, Trichuris trichiura. The soil fumigants methyl bromide, chloropircrin and Basamid or mixtures of  Basamid and chloropicrin proved to be of no use in filling T. trichiura ova in soil. However, on untreated plots the eggs died at a rate such than only 20% of the ova remained viable after 18 months.


A comparison of influenza and respiratory syncytial virus infections among infants admitted to hospital with acute respiratory infections. Among 741 children under 5 years admitted to hospital with respiratory infections during two winters, infection with influenza A virus was diagnosed in 70 (9%), with influenza B virus in 8 (1%), and with respiratory syncytial virus (RSV) in 259 (35%). Both influenza virus and RSV infections were diagnosed most frequently in children under the age of one year, and diagnosed more frequently in males than females. Influenza illnesses were more severe in boys than girls. Both infections occurred more often, but were not more severe, in children from a conurbation than in those from 'rural' areas. Convulsions were the cause of 36% of admissions with influenza A infections, but were rare in RSV infections. Bronchiolitis was the reason for 39% of admissions with RSV infections, but was rare in influenza infections. It is suggested that infants admitted to hospital are a good source of influenza virus strains for monitoring antigenic variation.


Laboratory evaluation of WBA 8119 as a rodenticide for use against warfarin-resistant and non-resistant rats and mice. Feeding tests were carried out in the laboratory to evaluate WBA 8119 as a potential new rodenticide against wild common rats (Rattus norvegicus), ship rats (R. rattus) and house mice (Mus musculus). The results obtained are compared with data previously obtained for difenacoum, another member of the same series of 4-hydroxycoumarin anticoagulants. With warfarin-resistnat and non-resistant common rats, complete kills were obtained using a concentration of 0-0005% for 2 days, or 0-001% for 1 day: a 1-day test at 0-0005% killed 6 out of 10 and 17 out of 20 of the two types respectively. At 0-0005% complete kills of resistant ship rats were obtained after 2 days exposure and of resistant house mice after 1 day, but at 0-002% for 2 days there was some survival. Non-resistant ship rats and house mice were all killed after 2 days feeding on 0-002% bait. In 2-day palatability tests, R. norvegicus showed no significant aversion to the poison at 0-002% and 100% mortality was obtained. The poison was significantly unpalatable to R. rattus at 0-005% and to M. musculus at 0-005% and 0-002%, although with the last species these concentrations gave complete kills. It is concluded that WBA 8119 has greater activity than other known anticoagulants against the three commensal species examined. The laboratory results suggest that concentrations between 0-0005% and 0-002% would be suitable for field use against common rats, and between 0-002% and 0-005% for ship rats and house mice.


The effect of cigarette smoking on susceptibility to epidemic influenza and on serological responses to live attenuated and killed subunit influenza vaccines. The effects of cigarette smoking on the incidence of epidemic influenza and on the serological response to influenza vaccination with killed subunit and live attenuated vaccines have been investigated during comparative vaccine trials in Western Australia. It was found that cigarette smokers with no pre-epidemic haemagglutination-inhibiting (HI) antibody (titres of less than or equal to 12) were significantly more susceptible to epidemic influenza than non-smokers. Smokers were no more susceptible however, if they had possessed detectable pre-epidemic HI antibody. A significantly higher proportion of smokers sero-converted after receiving the live virus vaccine than their non-smoking counterparts, but this could not be correlated with pre-vaccination HI antibody titres. The longevity of the immune response to the subunit vaccine was severely depressed 50 weeks post-vaccination in smokers who had possessed little or no immunity before vaccination (titres of less than or equal to 12). This antiboyd deficit was not observed in live virus vaccines or subunit vaccinees with pre-vaccination HI antibody (titres of greater than or equal to 24). Post-vaccinal symptoms were similar regardless of vaccine group or smoking history.


Trials of the anticoagulant rodenticide WBA 8119 against confined colonies of warfarin-resistant house mice (Mus musculus L.). The efficacy of the newly developed anticoagulant rodenticide WBA 8119 was evaluated against the house mouse (Mus musculus L.) using individual and family groups of warfarin-resistant animals. WBA 8119 at 0-002%, 0-005% and 0-01% in pinhead oatmeal bait gave complete kills of mice in 'no-choice' feeding tests carried out in cages and small pens. In replicated 21-day treatments on families of mice confined in larger pens conditioned to feeding on plain foods, the overall mortalities obtained using the three formulated poison baits were 71/72, 62/63 and 57/57 respectively. The results of the WBA 8119 toxicity tests are considered in relation to previous findings on other anticoagulant rodenticides, particularly difenacoum. In equivalents tests, WBA 8119 performed better than difenacoum. The data thus suport the laboratory findings that WBA 8119 is the most active anticoagulant so far tested for the control of warfarin-resistant house mice.


Trials of the anticoagulants rodenticide WBA 8119 against confined colonies of warfarin-resistant house mice (Mus musculus L.). The efficacy of the newly developed anticoagulant rodenticide WBA 8119 was evaluated against the house mouse (Mus musculus L.) using individual and family groups of warfarin-resistant animals. WBA 8119 at 0-002%, 0-005% and 0-01% in pinhead oatmeal bait gave complete kills of mice in 'no-choice' feeding tests carried out in cages and small pens. In replicated 21-day treatments on families of mice confined in larger pens and conditioned to feeding on plain foods, the overall mortalities obtained using the three formulated poison baits were 71/72, 62/63 and 57/57 respectively. The results of the WBA 8119 toxicity tests are considered in relation to previous findings on other anticoagulant rodenticides, particularly difenacoum. In equivalent tests, WBA 8119 performed better than difenacoum. The data thus support the laboratory findings that WBA 8119 is the most active anticoagulant so far tested for the control of warfarin-resistant house mice.


Restoration of endodontically treated posterior teeth.


Effect of endodontic procedures on the population of viable microorganisms in the infected root canal.


Histologic study of the effects of hydrocortisone on the apical periodontium of dogs.


Growth of bovine pulp cells in monolayer culture.


Systemic distribution of 210PbO from root canal fillings.


Extraoral fistulas of endodontic origin: report of two cases.


Realities of expectation--education and practice.


Stereotactic percutaneous cordotomy.

Stereotactic percutaneous cordotomy.


Accountability: the long road back to professional practice.


Third-party reimbursement.

Third-party reimbursement.


Report of the executive secretary, state board for nursing.


Studies on the relationship between FSH and germ cells: evidence for selective suppression of FSH by testicular extracts. The evidence supporting the relationship between the seminiferous epithelium and circulating FSH levels has been reviewed and provides support for the concept that the testis produces a factor capable of specifically controlling FSH concentrations. Detailed quantitative histological studies of the seminiferous epithelium have demonstrated a highly significant inverse relationship between the number of spermatogonia per tubule cross-section and serum FSH levels in men with testicular disorders.


Re-examination of the dependence of epididymal sperm viability on the epididymal environment.


New antiandrogens and their mode of action.


Secretion and role of androgen-binding proteins in the testis and epididymis. The Sertoli cell appears to be a target cell for both FSH and androgen. FSH stimulates the Sertoli cell to produce an androgen-binding protein (ABP) which may serve to increase the accumulation of androgen in the seminiferous tubular epithelium and make it available for binding by intracellular androgen receptors. This might be one way by which FSH enhances the action of androgen on spermatogenesis. Androgen acts on the Sertoli cell to increase its response to FSH resulting in increased production of ABP and of other substances which exert trophic effects on spermatogenesis.


Investigations into the physiology of the epididymis in relation to male contraception.


Retreat from death?

Retreat from death? The case of Terry Jenkins, a 15-year-old boy, who was found to have a sarcoma of bone, was discussed on television under the title of 'Inside Medicine'. The discussion revolved, not so much on the clinical details of the case or even of cancer of bone in a young person, as on the emotional disturbance that followed when the boy's mother refused to allow her son to be told about the nature of his illness or the proposed treatment. With hindsight, as is made clear in the discussion, the case should have been handled quite differently, with the general practitioner acting as the lynch pin and a psychiatrist and a social worker being brought into the emotional 'treatment' of the boy and his mother. As it was the boy was so disturbed about what he had guessed about his condition that he attempted suicide: fortunately he was rescued in time, and Terry is now stable, working, and mobile on his artificial leg.


Diagnosis problem of the month.

Diagnosis problem of the month.


Microhardness of human dentin: baseline values and effects of fluorides.


Guidelines for avoiding antitrust problems.


Establishing educational objectives for school based dental health education programs.


In vitro studies on the enhancement of Rauscher virus-induced erythroblastosis by complete Freund's adjuvant in BALB/c mice. Inoculation of complete Freund's adjuvant (CFA) into BALB/c mice either before or after infection with Rauscher murine leukemia virus (MuLV-R) led to an acceleration of the disease as determined by spleen weight. Treatment with CFA also induced a higher number of spleen erythroblast foci and, in the bone marrow, erythropoietin-independent cells that produced erythroid colonies in vitro. CFA induced in the bone marrow not only an increase in myeloid progenitor cells that can produce colonies in agar, but an ever larger increase in the number of erythroid colony-forming cells. Virus-induced erythroblastosis was probably enhanced by CFA due to the production of many target cells. The more primitive burst-forming cell, which produced large colonies of erythroid cells after 10 days in culture, was also physiologically transformed in MuLV-R-infected mice; bursts could be formed by cells of such animals in the absence of erythropoietin.


Monitoring of murine osteosarcoma by serial alkaline phosphatase determinations. To establish that alkaline phosphatase (AP) was released by osteosarcoma cells, we measured this enzyme in C3H/HeJ mice with im-implanted osteosarcoma and in in vitro cultures of neoplastic cells subjected to short-term incubation. We found that 10(5) osteosarcoma cells synthesized a significant amount of AP in vitro in 30 minutes at 37 degrees C. A good correlation existed between pulmonary metastatic tumors and the AP values. Serum AP measurements indicated approximate sizes of disseminated and localized tumors, but could not monitor early localized tumors.


Friend spleen focus-forming virus production in vitro by a nonerythroid cell line. We developed a cell line (IS) that continuously produced both Friend spleen focus-forming virus (SFFV) and XC plaque-forming virus in vitro. The line was derived from the enlarged spleen of an inbred SIM mouse previously infected with a polycythemic strain of Friend leukemia virus in vivo. Friend SFFV titers of 10(4) spleen focus-forming units/ml of culture medium were maintained for more than 200 cell generations. The virus from IS cells induced the splenomegaly and high hematocrit typical of Friend virus-induced erythroid disease in SIM mice. Cells of the IS line were adherent and phagocytic and had a low saturation density. They produced no tumors after being injected sc into normal syngeneic hosts and no spleen colonies after being injected iv into supralethally irradiated hosts. IS cells did not have the character of erythroid cells: They did not contain detectable heme as measured by benzidine-peroxide reagent, did not contain globin mRNA in detectable amounts, and did not produce erythroid colonies in plasma culture in the absence or presence of erythropoietin. According to these criteria, growth in the presence of dimethyl sulfoxide did not stimulate erythroid differentiation of IS cells. We concluded that Friend SFFV can infect nonerythroid spleen cells but that replication of the virus was not obligatorily coupled to expression of genes associated with the erythroid phenotype.


A periodontal abscess associated with vertical root fractures.


Ssytemic effects of intravenous polyriboinosinic-polyribocytidylic acid in man. To investigate the systemic, clinical and laboratory effects of iv polyriboinosinic-polyribocytidylic acid (poly I-poly C), 32 doses of poly I-poly C were administered to 22 patients. Doses between 1 and 10 mg/kg induced the formation of serum interferon (IF) and fever. Whereas a direct relationship was seen between the poly I-poly C dose and fever, serum IF levels were not significantly changed by increasing the dose of poly I-poly C over a log range from 1 to 10 mg/kg. Transient abnormalities were noted in liver function tests in 4 of 13 patients who received greater than 6.0 mg/kg. Other laboratory changes were confined to an increase in the absolute granulocyte count that paralleled fever development and abnormalities in coagulation parameters of 1 patient. In vitro lymphocyte DNA synthesis in response to mitogens was transiently impaired at times corresponding to serum IF appearance. These studies have established dose levels of poly I-poly C that can be safely administered to man with minimal toxicity and result in IF induction.


Occurrence of spontaneous tumors in the germfree F344 rat. The incidence of spontaneously occurring neoplasms was observed over 10 years in a colony of germfree F344 rats (78 males and 102 females) representing 10 generations of inbredding. Leukemia was the most common neoplasm (25.6% of males, 36% of females) followed by mammary tumors (11.5% of males, 19.6% of females). Various other tumors developed in 9% of the males and 5% of the females. The overall incidence of spontaneous tumors was comparable to that reported for conventional rats of different strains. This was particularly true of leukemia for which the most data were available. However, for unknown reasons, significantly fewer solid tumors were observed in germfree than in conventional male rats.


Effectiveness of pit and fissure sealants in the prevention of caries.


Dental practice management and taxes.

Dental practice management and taxes.


The get-well stay-well diet.

The get-well stay-well diet.


Cariostatic effects of fluoride mouthrinses in a non-fluoridated community.


Support the relief fund.

Support the relief fund.


Diagnostic yield in dental radiology.

Diagnostic yield in dental radiology.


Dentistry continues to change.

Dentistry continues to change.


Guest editorial.

Guest editorial.


Opening remarks. Twenty-seventh annual dental health workshop.


Insurance industry and your private dental practice--background experience of involved physicians.


The importance of mutual understanding in third party plans.


Peer review: private practice's first and last line of defense.


Name your own poison.

Name your own poison.


Emphysematous gastritis in a leukemic child. Emphysematous gastritis associated with gram-negative sepsis is described in a leukemic child on chemotherapy and steroids. Bubbly-appearing air and thickening of the gastric wall were radiographically demonstrated. This is analogous to the demonstration of air within the thickened bowel wall in necrotizing enterocolitis, which is not unusual in seriously ill leukemic children. Gastric involvement has not been previously reported.


Immunocompetence and prognosis in children with acute lymphoblastic leukemia: combination of two different maintenance therapies. Intensive chemotherapy in patients with leukemia produced immunosuppression. The level of immunocompetence correlates with prognosis. The immunological function of 29 children with acute lymphoblastic leukemia (ALL) in complete remission and on 2 different maintenance therapies was evaluated and compared with 16 normal children (Group A). Sixteen children (Group B) with ALL received 6 mercaptopurine (6MP) daily and methotrexate (MTX) twice a week, and 13 children (Group C) received 6MP and MTX weekly for maintenance. There was depression of both cellular immunity, measured by the number of T cells and skin tests, and humoral immunity, measured by number of B cells, primary antibody production to typhoid vaccine, and levels of immunoglobulins. However, continuous maintenance therapy (Group B) produced significantly more severe immunosuppression of cellular immunity than the intermittent therapy (Group C). Humoral immunity was equally depressed in both groups of leukemia patients, but was less altered than cellular immunity. Concomitantly, patients with intermittent maintenance chemotherapy had less hematologic depression, fewer episodes of infection, and fewer died in complete remission. Patients of both groups with higher levels of immunocompetence had better prognosis with longer duration of complete remission than patients with severe immunosuppression. Out of 6 patients with "favorable immunocompetence" only 1 relapsed at 7 months and the other 5 remain in complete remission from 8 to 31 months. Among 23 leukemic patients with "unfavorable immunocompetence," 15 relapsed and 8 remain in complete remission from 9 to 26 months.


Venomous snakebites of the extremities.

Venomous snakebites of the extremities.


Pulmonary aspiration -- a life-threatening complication in obstetrics.


Partial denaturation mapping of cloned histone DNA from the sea urchin Psammechinus miliaris. A cloned 5.6-kb DNA repeat unit of Psammechinus miliaris containing all five histone coding sequences of known order and polarity has been shown to fall clearly into a low melting and a high melting half by thermal denaturation. The topoligies of the DNA sequences thus defined were determined by partial denaturation mapping in the electron microscope to gain further insight into the distribution of spacers and genes within histone DNA.


The retrosternal foramen of Morgagni: massive small bowel herniation.


Management of streptococcal pharyngitis by North Carolina physicians.


The autumnal high: jimsonweed in North Carolina.


Unusual encephalitic illnesses in a child with acute leukaemia in remission: possible role of measles virus and Toxoplasma gondii. We report a girl who developed an encephalitic illness with visual loss after two years treatment for acute lymphoblastic leukaemia. The visual loss was found to be due to bilateral macular degeneration. She later developed radiological evidence of intracranial calcification and temporal lobe epilepsy. A second episode of encephalitis occurred when she had been off all antileukaemic treatment for three years and this left her with a right hemiparesis. Investigation suggested involvement with both measles virus and Toxoplasma gondii as a cause for these illnesses.


Screening and presymptomatic diagnosis in clinical practice.


Gastric bypass for morbid obesity.

Gastric bypass for morbid obesity. Failure of conservative methods of control of gross obesity has led to the adoption of surgical measures. The operation of intestinal bypass, may be associated with the number of unpleasant complications. As a result there has been recent interest in the operation of gastric bypass involving an 80 to 90 percent gastric exclusion procedure. We report on the results of our first 19 patients undergoing this operation, a six to 15 month follow-up. The early results would suggest that gastric bypass in the treatment of morbid obesity is likely to prove superior to the various forms of intestinal bypass.


Injury to the rectum.

Injury to the rectum.


Objective respiratory screening among Dunedin public servants. The results of a questionnaire concerning respiratory symptoms in Dunedin public servants have been reported earlier (de Hamel, O'Donnell, 1972). This report is of the results of spirometry in the same population. Fifty-five percent of 1079 men and 59 percent of the 310 women with normal mass miniature chest x-rays showed an FEV 1.0 below the predicted value, but in only 9 percent of each sex was the FEV 1.0 less than 80 percent of predicted. Bronchitic symptoms and a history of regular cigarette smoking were associated with an impaired FEV 1.0. The FEV 1.0 was normal in many giving a history of the bronchitic symptoms cough, phelgm or wheezing. The FEV 1.0 of overweight men was not significantly different from the other men. Attention is drawn to the high frequency of chronic bronchitis in the population and the correlation of this with moderate and heavy cigarette smoking. The questionnaire disclosed more abnormality within the population than did the spirometrey. They may complement one another when effort is being directed at health education.


Treatment success in alcoholism.

Treatment success in alcoholism. Two hundred and sixty-two male and 51 female alcoholics treated in 1971 were followed up for two years: 71 percent of the sample were contacted: 43.5 percent males were abstinent or improved: 56.7 percent of the females were abstinent or improved. Treatment success was co-related with being married, being in the upper socio-economic groupings, and staying for the full 12 week inpatient course. Repeated failure in treatment was associated with being single, of low socio-economic status, and with one previous admission for alcoholism. It is suggested that the main factor in the increasing prevalence of alcohol problems in the general population is the relative cheapness of liquor.


Digoxin poisoning: case report.

Digoxin poisoning: case report. Digoxin overdose leading to toxicity causes a variety of symptoms ranging from cardiovascular, gastrointestinal and central nervous system effects. Toxicity occurs at a serum level of 3.0ng/ml. The value of phenytoin sodium in treatment of digoxin toxicity is discussed.


The need to train anaesthetists in New Zealand. A survey of New Zealand public hospitals undertaken at the end of 1974 shows that the country is training half the number of anaesthetists to maintain the public hospital-based anaesthetic services. There is a need to develop and expand training programmes for anaesthetists. New graduates can be assured that there are career prospects in the specialty.


Comparison of a slow release formulation of oxprenolol with conventional oxprenolol in the treatment of hypertension. Patients with moderate to severe hypertension were studied during a 12-week period, during which they were given a slow release formulation of oxprenolol once daily, in a dosage equal to their previous total daily dose of oxprenolol given in divided doses. There were no systematic differences between blood pressures at the beginning and end of the 12-week period. The once-daily dosage was well tolerated and was preferred by the patients. This regime offers advantages in terms of patient compliance with lifelong therapy in what is usually a symptomless condition.


Haemophilia: no longer a crippling disease, Charles Norwood lecture.


Early complications after mild head injuries.


An assessment of the need for vaccination amongst junior medical staff. This study was set up to determine the susceptibility of junior medical staff to communicable infectious diseases. Thirteen female and 39 male staff were investigated. Antibodies to morbilli, varicella zoster, toxoplasma, cytomegalovirus, hepatitis B, mumps and rubella were determined. Hepatitis B surface antigen tests were also carried out. Twelve males were susceptible to mumps and 10 were subsequently vaccinated. No side effects were noted. Three of five females susceptible to rubella requested vaccination and all showed an antibody response without early or delayed side effects. The desirability of offering vaccinations to susceptible adult staff is discussed.


Coronary heart disease.

Coronary heart disease.


Are 24-hour urine collections necessary for the measurement of steroid excretion rates? In the assessment of ovarian activity, testicular response in human chorionic gonadotrophin (HCG), and placental and fetal viability during pregnancy, measurements made on small samples of urine may be used to monitor changes in 24h steroid output; the collection of 24h urine specimens is not necessary. For women, 24h output approximately 10 R (R, steroid/creatinine in small urine samples; concentrations expressed in SI units of amount). For men, 24h output approximately 14 R.


Safety glass on the road.

Safety glass on the road.


Maternity services.

Maternity services.


Acupuncture.

Acupuncture.


Leptospira interrogans serovar tarassovi in New Zealand.


The continuing education needs of general practitioners.


Re-instatement of regular defecation routines in a four-year-old boy. A four-and-a-half year old boy was withholding faeces for up to eight days. A programme of positive reinforcement contingent upon his being placed on the toilet according to a schedule was introduced. An operant technique of immediate, positive reinforcement was utilised to reward bowel movements. Results indicate that the reinstatement of a two-daily routine of defection was achieved after 48 days. The programme was introduced and maintained by the child's mother with no outside intervention in the routine.


Deep vein thrombosis after femoropopliteal bypass grafting with observations on the incidence of complications following the use of dextran 70. Radiological thrombosis was demonstrated on six occasions in the leg veins in 66 patients following the placement of 71 femoropopliteal bypass grafts. All patients received dextran 70 as prophylaxis postoperatively. The incidence was similar for grafts with the lower anastomosis either above or below the knee joint. No predisposing factors to venous thrombosis were apparent other than blood dyscrasias. A further group of patients who had arterial reconstructive procedures were examined to determine the incidence of the complications of bleeding and heart failure which might be attributed to the routine use of dextran 70. The incidence of complications in this larger group indicates that the routine use of dextran 70 is not a significant factor in their occurrence in the postoperative period.


The reduction of soiling behaviour in an 11-year-old boy with the parent as therapist. An 11-year-old boy who had soiled daily for six years since entering school had threatened to commit suicide. Following an initial assessment, a parent was trained to monitor an experimental procedure that effectively reduced soiling to a level where the only occurrence noted in two months resulted from a bout of diarrhoea.


A blueprint for doctors.

A blueprint for doctors.


Medical students design their ideal medical school. New Zealand medical students were asked to design the ideal medical school. The areas they marked for change included candidate selection, curriculum, teaching standards and methods of assessment. They suggested ways of making medical training a more personal, broader and better integrated experience. The rigid division between pre-clinical and clinical studies was criticised as were time-wasting lectures and rapid-fire lecturers. The students' recommendations were similar to many which have appeared in the literature of medical education.


Responsibility and medical practice.

Responsibility and medical practice.


Resources for psychiatry.

Resources for psychiatry.


Lead poisoning caused by glazed pottery: case report. A case of severe lead poisoning is described. This was caused by the ingestion of fruit drink prepared and stored in lead-glazed jugs. Results of tests to measure the extractability of lead from the jugs are given.


Thoracic and arterial pressures, blood flow and syncope. The relationship between elevation of the thoracic pressure and the thoracic volume and blood pressure was investigated in man. Raising the thoracic pressure produced an increasing hypotension and ultimately fainting. Cine-radiography showed a reduction in heart size while the high thoracic pressure was maintained.


Thermoregulation during mild exercise.

Thermoregulation during mild exercise. A comparison was made of the thermoregulatory effects of wearing black or white clothing during exercise under radiant heating. For subjects in black clothing the skin temperature was higher than with white but the rectal temperature and heart rate were lower.


A family case study.

A family case study.


Blood volume and exercise in dogs.

Blood volume and exercise in dogs. The plasma volume and haematocrit ratio were examined in dogs during exercise. The plasma volume increased after exercise and persisted for 10 minutes on its cessation. There was a 14 percent increase in the haematocrit ratio.


Raynaud's phenomenon of the nipples.

Raynaud's phenomenon of the nipples.


Facts about multiple sclerosis. Part I.

Facts about multiple sclerosis. Part I.


The ward sister--a vital role in the health care team.


First, you tell them---.

First, you tell them---.


Sleep deprivation as a therapy for depressed patients.


Ward pharmacy--Southland Hospital.

Ward pharmacy--Southland Hospital.


Evaluation of student nurses--is it worth the effort?


Social consequences of multiple sclerosis. Part 2.


Nursing care of a patient admitted for cholecystectomy.


Can the multiple sclerosis patient be further helped. Part III.


Policy on post-basic nursing education.

Policy on post-basic nursing education.


Curriculum evaluation in nursing.

Curriculum evaluation in nursing.


Sleep deprivation as a therapy for depressed patients. Part II.


Osteopathy due to methotrexate.

Osteopathy due to methotrexate. Two children with ALL receiving long-term therapy with methotrexate (50 mg/week i.v.) developed severe osteoporosis accompanied by swelling of the joints, gait disturbances and fractures after minimal trauma. Bone scans 85Sr disclosed a decreased input and increased turnover of calcium especially in the most used bones. The data of the calcium phosphorus metabolism are within the normal range. The minimal changes in the biopsy material of the iliac crest may be due to little mechanical use so that this part of the skeleton is not much affected by the osteoporosis. Since the controls receiving the same therapy did not have signs of such severe osteoporosis it is assumed that an additional, till unknown factor may play an additional role in this kind of methotrexate side effect.


The change to encapsulated amalgam.

The change to encapsulated amalgam.


Photography for reproduction in magazines and periodicals.


H.S.S. report.

H.S.S. report.


Dental prepayment: friend or foe?

Dental prepayment: friend or foe?


The state of the art.

The state of the art.


Prediction of relapse and remission in AML by marrow culture criteria. Bone marrow culture studies in semi-solid agar have been performed on 250 patients presenting with acute myeloid leukemia. The detection of a spectrum of qualitative defects in the proliferation, differentiation and biophysical characteristics of leukemic colony forming cells (CFU-c) has permitted a detailed analysis of the relapse-remission status based on transition from qualitatively abnormal cell growth in vitro to a normal pattern of proliferation and differentiation. Changes in vitro generally preceded clinical or morphological evidence of the onset of relapse or remission and serve as a valuable additional parameter in monitoring clinical status. Marked cyclic changes in CFU-c incidence appeared to characterize the remission phase of AML and were frequently associated with fluctuations in marrow blast cell count which can lead to mis-diagnosis of incipient relapse. Detection of qualitative defect in marrow culture serves to distinguish patients with preleukemic disorders at high risk of termination in acute myeloid leukemia from patients with clinically similar disease who have not undergone further progression over a 2-4 year period of observation.


Significance of PHA induced clonogenic cells in chronic myeloid leukemia and early acute myeloid leukemia. A technique for cloning myeloblastic leukemic cells in semi-solid agar, after prior PHA stimulation, was studied in all phases of chronic myeloid leukemia. Phytohemagglutinin responsive cells were found in blast crisis and accelerated phase. In a small number of patients in the benign phase of their disease, colony growth with PHA was detected. A group of patients with early acute leukemia was also examined by this technique. The incidence of PHA colonies appeared to correlate with the progression of the disease. The potential application of this assay for early detection of leukemic clones and possible prediction of the rapidity of progression of the leukemic process is discussed.


Acute myeloblastic leukemia after immunodepressive therapy for primary nonmalignant disease. Three patients treated with immunodepressive chemotherapy over a period of 43, 60, 38 months respectively, for primary nonmalignant disease, developed AML after cessation of chemotherapy. During the months preceding the AML outbreak, there were hematologic changes with seemed to reveal a preleukemic state. Our 3 patients, and 8 previously published cases, making a total of 11 patients, developed AML after chemical immunodepression for reasons which were neither hematologic nor neoplastic.


Preleukemia: does it exist?

Preleukemia: does it exist? In acute myeloid leukemia (AML), many of the remaining normal-appearing cells exhibit various abnormalities. An interpretation is that these cells are descendants of leukemic cells which have succeeded in overcoming the major final differentiation block that exists in AML. Direct evidence is quoted that red cell precursors in AML are of leukemic descent and it is claimed that the target cell of AML is the pluripotent stem cell. Next, evidence has been compiled that all three cell lines (red cell, n. granulocytes, platelets) exhibit qualitative defects in "prelukemia." Hence it is postulated that preleukemia per se doses not exist but that preleukemic states which with a rather high frequency sooner or later end in overt AML are actually true leukemias that, however, differentiate reasonably well. Another way of phrasing it is that preleukemic states are AMLs that present in partial and sometimes long-lasting remission, which only after months to years lose their differentiation ability and then are classified as AML.


Comparative electron-microscopic study of the erythrocytic line in refractory anemia (preleukemia) and myelomonocytic leukemia. The bone marrow erythrocytic precursors of 12 patients with refractory anemia (preleukemia) or myelomonocytic leukemia were studied by transmission electron microscopy. The results were tabulated in a semiquantitative manner and a comparison was established between the two main diagnostic groups. The following results are reported. 1. Similar nuclear and cytoplasmic abnormalities of the normoblasts were observed in preleukemia and leukemia. 2. A nuclear lesion consisting of nuclear clefts and blebs was demonstrated in at least some of the normoblasts in all of the patients. Although not specific, this finding appears to be a new contribution in the field of preleukemia and myelomonocytic leukemia. 3. Iron overload, including the presence of pathologic sideroblasts, is common to both preleukemia and leukemia.


Prediction of three-dimensional structures of enzyme-substrate and enzyme-inhibitor complexes of lysozyme. Conformational energy calculations were used to predict the three-dimensional structures of enzyme-substrate and enzyme-inhibitor complexes of lysozyme. A global search method, involving the use of a disaccharide fragment molecule, was used initially to determine all favorable binding regions at the active site. It is shown that the binding of a series of (nonfragmented) oligomers of N-acetylglucosamine is highly specific. The results show further that (a) the enzyme recognizes only one backbone conformation of the oligomer, corresponding to a left-handed helix, and (b) for saccharides containing two or more N-acetylglucosamine residues, two residues bind preferentially to the C and D sites. The calculations also suggest that the chair form of N-acetylglucosamine can bind to the D region. The saccharide residues of tetra-N-acetylglucosamine bind to the A-B-C-D sites, with the residues at the A-B-C sites having essentially the same conformation and orientation as those in the x-ray structure of tetra-N-acetylglucosamine-delta-lactone bound to lysozyme.


Theoretical studies of the conformational properties of ribavirin. One of the factors required for the antiviral activity of the synthetic nucleoside, ribavirin (1-beta-D-ribofuranosyl-1,2,4-triazole-3-carboxamide), is the ability of the molecule to adopt the substrate conformation specified by the enzyme for which it is a competitive inhibitor, inosine 5'-phosphate dehydrogenase (IMP:NAD+ oxidoreductase, EC 1.2.1.14). The calculated glycosidic minimum for ribavirin is the high syn conformation, which is in agreement with experimental determinations of the molecule's solution conformation. The similarity in solution between the conformation of the active ribavirin molecule and the conformation of its inactive 5-methyl and 5-chloro derivatives indicate that some other substrate conformation is specified by the enzyme. The high anti conformation, found by these calculations to be close in energy to the high syn minimum, is postulated to be the active conformation required by the enzyme. The inactivity of the 5-methyl and 5-chloro derivatives is attributed to the much greater stability of these derivatives in the inactive high syn conformation.


Modeling the resonance Raman spectrum of a metarhodopsin: implications for the color of visual pigments. Resonance Raman spectra of an invertebrate rhodopsin are reported. The spectrum of squid acid metarhodopsin is compared with the spectra of model compounds of the retinylidene chromophore in the all-trans conformation. Correlations made between acid metarhodopsin and these crystalline model compounds with known x-ray structures indicate that the chromophore in this intermediate is an all-trans protonated Schiff base. The data suggest a mechanism for the red shift in rhodopsin.


Structural characterization of a bridged 99Tc-Sn-dimethylglyoxime complex: implications for the chemistry of 99mTc-radiopharmaceuticals prepared by the Sn (II) reduction of pertechnetate. Reduction of pertechnetate by tin(II) in the presence of dimethylglyoxime is shown, by single crystal x-ray analysis, to yield a technetium-tin-dimethylglyoxime complex in which tin and technetium are intimately connected by a triple bridging arrangement. One bridge consists of a single oxygen atom and it is hypothesized that this bridge arises from the inner sphere reduction of technetium by tin(II), the electrons being transferred through a technetium "yl" oxygen which eventually becomes the bridging atom. Two additional bridges arise from two dimethylglyoxime ligands that function as bidentate nitrogen donors towards Tc and monodentate oxygen donors towards Sn. The tin atom can thus be viewed as providing a three-pronged "cap" on one end of the Tc-dimethylglyoxime complex. The additional coordination sites around Tc are occupied by the two nitrogens of a third dimethylglyoxime ligand, making the Tc seven-coordinate. The additional coordination sites around Sn are occupied by three chloride anions, giving the Sn a fac octahedral coordination environment. From indirect evidence the oxidation states of tin and technetium are tentatively assigned to be IV and V, respectively. Since most 99mTc-radiopharmaceuticals are synthesized by the tin(II) reduction of pertechnetate, it is likely that the Sn-O-Tc linkage described in this work is an important feature of the chemistry of these species. This linkage also provides a ready rationale for the close association of tin and technetium observed in many 99mTc-radiopharmaceuticals.


Segment-long-spacing aggregates and isolation of COOH-terminal peptides from type I procollagen. Type I procollagen secreted by matrix-free cells from chick embryo tendons was purified by DEAE-cellulose chromatography. Electron microscopy of segment-long-spacing aggregates of the procollagen demonstrated the presence of both NH2-terminal and COOH-terminal extensions not found in collagen. The procollagen was digested with bacterial collagenase and the COOH-terminal fragments were isolated by gel filtration and polyacrylamide gel electrophoresis in sodium dodecyl sulfate. Analysis of tryptic peptides demonstrated that the COOH-terminal extensions on the pro alpha 1 and pro alpha 2 chains had different primary structures.


Free acid, anion, alkali, and alkaline earth complexes of lasalocid a (X537A) in methanol: structural and kinetic studies at the monomer level. We report below on nuclear magnetic resonance investigations of the structure and exchange kinetics for the free acid, anion, sodium complex, and barium complex of the ionophore lasalocid A (X537A) in methanol solution. A comparison between the proton and carbon longitudinal relaxation times of lasalocid in nonpolar and polar solvents demonstrates that the free acid (HX) is a monomer in methanol solution. Parallel proton and carbon relaxation measurements demonstrate that the anion (X-), sodium complex (NaX), and barium complex (BaX+) are also monomeric in methanol solution. These results are in contrast to the Na2X2 dimer and the BaX2-H20 dimer observed in crystals and in nonpolar (cyclohexane and methylene chloride) solutions. Large downfield shifts on complex formation (X- to NaX and BaX+) are detected for protons located on the polar face of the ionophore with their C-H bonds directed towards and proximal to the metal ion. The exchange of lasalocid anion between free (X-) and complexed (BaX+) states in methanol can be monitored from the temperature-dependent line shapes of the proton resonances at superconducting fields. The exchange rates are independent of the reactant concentrations and are characteristic of a rate-determining dissociation of BaX+ in methanol solution with activation parameters delta H++ = 6.5 kcal mol-1 (25 degrees) and delta S++ = -20.0 cal mol-1 degree -1 (1 cal = 4.184 J). The rate constants for dissociation and formation of BaX+ complex in methanol, 25 degrees, are 5.2 X 10(3) sec-1 and 1.5 X 10(10) M-1 sec-1, respectively. These studies were extended to derive the activation parameters for the exchange of lasalocid anion between BaX+ and NaX and between BaX+ and HX in methanol, while the exchange among HX, X-, and NaX is too rapid to be monitored on the time scale of nuclear magnetic resonance.


DNA unwinding component of the nonhistone chromatin proteins. A subclass of nonhistone chromatin proteins from rat liver, previously shown to exhibit high affinity for DNA, has been fractionated by single-stranded DNA-agarose affinity chromatography. The protein fraction that bound to DNA-agarose in 0.19 M NaCl-buffer and was eluted with 2 M NaCl-buffer is enriched for a protein component of approximately 20,000 daltons and exhibits preferential binding to denatured DNA. This nonhistone protein fraction specific for single strands binds to DNA in a non-species-specific manner, and causes helix-coil transition of synthetic poly[d(A-T)-d(A-T)] at 25 degrees, as indicated by the increase in absorbance of ultraviolet light at 260 nm. The observed hyperchromicity does not result from any nuclease activity in the protein fraction, because addition of Mg+2 results in partial hypochromic shift, and the protein/DNA complex is retained by nitrocellulose filters.


Regulation of protein synthesis in rabbit reticulocyte lysates: purification and initial characterization of the cyclic 3':5'-AMP independent protein kinase of the heme-regulated translational inhibitor. The heme-regulated translational inhibitor (HRI) has been purified 4800-fold. On electrophoresis in sodium dodecyl sulfate/polyacrylamide gel, the purified HRI showed one major polypeptide band. The purified HRI inhibits protein synthesis in lysates containing optimal levels of hemin with inhibition kinetics which parallel those observed in heme-deficiency. Data are presented which are consistent with an enzymatic function of HRI in the inhibition of protein synthesis. The HRI is an adenosine 3':5'-cyclic monophosphate independent protein kinase which phosphorylates the small subunit (38,000) but not the large subunits (52,000 and 50,000) of the initiation factor which forms a ternary complex with Met-tRNAf and GTP. This evidence supports the hypothesis that inhibition of protein synthesis by HRI involves the phosphorylation of the initiation factor. These findings are discussed in relation to various models for the regulation of protein kinase activity by heme. (see article).


Immunological characterization of the subunit of the 100 A filaments from muscle cells. We report the immunological characterization of the subunit of the intermediate sized (100 A) filaments from muscle cells. The protein as isolated from smooth muscle (chicken gizzard) has an apparent molecular weight of 50,000. It is insoluble in buffers that solubilize myosin and the majority of actin, but becomes soluble in the presence of urea. Under a variety of experimental conditions, that include the presence of 8 M urea, this new protein comigrates with actin during purification studies. The two proteins can be separated from each other by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, and antibodies have been elicited against the 50,000 dalton protein purified by using this technique. These antibodies crossreact with the partially purified protein in urea, but show no detectable cross reaction with actin or myosin. Indirect immunofluorescence reveals that in skeletal muscle this protein is found in close association with the Z lines of the sarcomeres and extends between the Z lines of adjacent myofibrils; it is also associated with filamentous structures that run along the length of a muscle fiber both in close association with the plasma membrane and between myofibrils at the level of their Z lines. In heart muscle, the protein shows the same distribution as in skeletal muscle. In addition, it is found intimately associated with intercalated disks and areas of membrane interaction between laterally associated heart muscle cells. The immunofluorescent localization to the subunit of the 100 A filaments suggests that in muscle cells this molecule may serve to link actin filaments at the level of the Z line (or intercalated disk) with the muscle plasma membrane. We believe that it functions in muscle primarily as a three dimensional matrix which interconnects individual myofibrils to one another and to the plasma membrane at the level of their Z lines. In this manner, this molecule may provide a framework that mechanically integrates all the contractile myofilaments during the contraction and relaxation of muscle. As a means of indicating its linking role in muscle, we have termed the protein desmin (from the Greek delta epsilon sigma mu os = link, bond).


Interactions of heterologous nitrogenase components that generate catalytically inactive complexes. A unique method is described for inhibiting nitrogenase. When Clostridium pasteurianum nitrogenase is assayed in the presence of the Mo-Fe protein of Azotobacter vinelandii, all the characteristic activities of nitrogenase are inhibited. C. pasteurianum nitrogenase is unaffected by the Fe protein of A. vinelandii. The Fe protein, but not the Mo-Fe protein of C. pasteurianum, inhibits A. vinelandii nitrogenase. Both inhibitions described result from the formation of an inactive complex of A. vinelandii Mo-Fe protein and C. pasteurianum Fe protein. Complex formation requires active components, as oxygen-denatured proteins are ineffective. The results for titration of components of the complex against each other and kinetic data each indicate that the inactive complex consists of two molecules of C. pasteurianum Fe protein per molecule of A. vinelandii Mo-Fe protein. The results of kinetic experiments suggest that the Fe protein from each organism competes for the same site(s) on the A. vinelandii Mo-Fe protein. The Fe protein of C. pasteurianum will form an active or an inactive complex with the Mo-Fe proteins from six different organisms. Inhibition by nitrogenase components that form inactive complexes provides numeroius ways to study the mechanism of nitrogenase action.


Amino-terminal sequences of two polypeptides from human serum with nonsuppressible insulin-like and cell-growth-promoting activities: evidence for structural homology with insulin B chain. The amino-terminal sequences of two polypeptides with nonsuppressible insulin-like and cell-growth-promoting activities (NSILA I and II), isolated from human serum, were determined. Of the first 31 residues, 22 are identical in NSILA I and II. Moreover, a striking structural similarity was found between NSILA and insulin B chain: 47 and 57% of residues 1-30 in NSILA I are identical to those in insulin B chain from man and tuna fish, respectively. This high degree of sequence identity is presented as evidence for homology and thus for a common evolutionary origin of insulin and NSILA. Based on these results and on these results and on biological properties of NSILA described earlier, a new designation for NSILA is proposed: insulin-like growth factor (IGF).


Coupling of catecholamine receptor from one cell with adenylate cyclase from another cell by cell fusion. The experiments test the hypothesis that beta-adrenergic receptor is an independent unit that can be transferred from one adenylate cyclase [ATP pyrophosphate-lyase (cyclizing), EC 4-6-1-1[ system to another. Turkey erythrocytes in which the catalytic activity of adenylate cyclase had been inactivated by N-ethylmaleimide or by heat contributed the beta-adrenergic receptor. Friend erythroleukemia cells (F cells) that possessed no measurable beta-adrenergic receptor contributed the adenylate cyclase. The erythrocytes in which the enzyme had been inactivated were fused with the F cells by Sendai virus. The cell ghosts of the fused preparation demonstrated adenylate cyclase activity which was strikingly enhanced by isoproterenol. Controls of fusion of F cells with each other or with human erythrocytes failed to show a response to isoproterenol. It was therefore concluded that the beta-adrenergic receptor of the turkey erythrocytes must have become functionally coupled to the adenylate cyclase of the mouse F cells. Activation by isoproterenol was demonstrable within a few minutes after fusion, and inhibitors of protein synthesis had no effect. Thus, coupling must have occurred between the preexisting components. The findings suggest that it may be possible in the future to confer on cells that possess an adenylate cyclase system new hormonal responses by inserting a receptor into their cell membrane. It is proposed that the procedure of massive heterologous cell fusion, as used in the present study, can be used to analyze the function of other cell membrane components.


Brain tubulin polymerization in the absence of "microtubule-associated proteins". Pure tubulin dimer, purified by phosphecellulose chromatography to remove microtubule associated proteins, can be assembled into microtubules in the presence of dimethyl sulfoxide. The surfaces of such microtubules are devoid of filamentous material. The reaction is rapid and strongly dependent on protein concentration. No microtubule formation occurs from the purified tubulin when dimethyl sulfoxide is omitted.